The Secretary of State for Defence (Dr Liam Fox)
As part of his statement on the strategic defence and security review (SDSR) on 19 October 2010, my right hon. Friend the Prime Minister said that we had reviewed our deterrence requirements and concluded that we could meet the requirement for an effective and credible deterrent with a smaller number of nuclear weapons and over the next few years would reduce the scale of the current deployed capability, incorporating this reduction into plans for the successor submarine. Therefore, we would reduce the number of warheads on board each submarine from a maximum of 48 to a maximum of 40, reduce the number of operational missiles in the VANGUARD class submarines to no more than eight, and reduce the number of operational warheads from fewer than 160 to no more than 120.
I wish to inform the House that the programme for implementing the SDSR warhead reductions has commenced: at least one of the VANGUARD class ballistic missile submarines (SSBN) now carries a maximum of 40 nuclear warheads. The programme of work to complete these changes across the VANGUARD SSBN fleet will be completed within the constraints of the deterrent’s operational programme. We currently expect completion to be made within this Parliament. The Government do not comment upon the operational programme and therefore updates on this implementation programme will not be given. I will update the House further once the changes have been completed across the current SSBN fleet and the SDSR commitment to reducing our stock of operationally deployed warheads has been fulfilled. On current plans, our expectation is that the subsequent reduction in our total stockpile to no more than 180 warheads will be completed by the mid 2020s.
The early commencement of the programme for these reductions in warheads is a significant step and further demonstrates the Government’s commitment to fulfilling the UK’s disarmament obligations under the nuclear non-proliferation treaty. The Government remain committed to maintaining the minimum credible deterrent necessary to achieve our deterrence objectives of guaranteeing national security.